Canadian patent No 704,837 issued in 1965 to the present assignee, discloses an automotive snow blower truck, provided with a front collector frame unit, defining a front mouth. When the truck moves forward, incoming ground-standing snow enters into the collector unit through the front mouth thereof. Two horizontal endless screws, superimposed over one another, are carried inside the collector unit for capturing and crushing incoming snow and ice, and for conveying the crushed snow and ice toward a snow-ejecting fan outlet made intermediately of the back wall of the collector unit. Each endless screw includes a power-driven shaft and two elongated sheet members, integrally mounted to the shaft and spiralling therealong. Additional spiralling sheet members are provided to reinforce the first sheet members. The claimed purpose of the reinforcing sheet members is to positively prevent structural deformation of the spiralling sheet members, when the rotating sheet members are operatively crushing the incoming snow and ice.
It is natural for (unloaded) one-entry endless spiralling screws of snow blower trucks not to be balanced, which means that these screws will vibrate and jump upon rotation thereof. To alleviate this problem, weight members are conventionally added to the exterior face of the spiralling screw, at selected locations, in order to compensate for the imbalance. However, such weight members, because they project exteriorly of the outer surface of the spiralling screw, do form physical obstructions to the free movement of the ice and snow conveyed by the spiralling screw. Such obstructions decrease the efficiency and durability of the spiralling screw.